Grating edge structure



Oct. 22, 1929. NAGIN 1,732,527

GRAT ING EDGE S TRUCTURE Filed June 27. 1927 lttlt lid Patented Oct. 22, 1929 UNITED STATES PATENT OFFICE OF PITTSBURGH, PENNSYL VANIA, A CORPORATION OF IEENNSYLVANIA GRATING EDGE STRUCTURE Application filed June 27, 1927. Serial No. 201,703.

This invention relates to grating edge structures and particularly to an edge structure for gratings employing girder bars and cross bars.

A grating of this character is described and claimed in my Patent No. 1,631,691, June 7, 1927. The invention is herein described as particularly applied to such grating structure, but it will be understood that it has numerous other applications.

Those gratings which employ girder bars and cross bars depend upon some form of joint between the bars to hold the grating together as distinguished from gratings employing corrugated members which lie between the girder bars and are riveted thereto. Tn the cross bar type of grating it has heretofore been necessary to extend the cross bars a short distance beyond the girder bar at the edge of the grating in order to insure a proper joint. Where this construction was undesirable, it was necessary to weld the outside girder bar to the cross bars or else to resort to riveting between the girder bar and the cross bars.

T provide a grating whose cross bars have projecting end portions, these projecting portions being so bent as to engage the girder bar and prevent displacement thereof. Preferably, the projecting cross bar portion is bent into general parallelism with the girder bar and in contact therewith.

The type of gratingdisclosedin my prior patent comprises girder bars having curved slots therein and straight cross bars forced into the slots so as to form locking tongues which permanently secure the parts together. Where this type of grating is used there is a particularly strong joint secured at the edge girder bar. At the same time, the joint is not open to the objection that sharp ends of cross bars project.

In the accompanying drawings illustrating the present preferred embodiment of my invention and one modification thereof, Figure 1 is'a top plan view partly broken away showing my invention applied thereto;

Figure 2 is a side elevation of Fig. 1; and Figure 3 is a View similar to Fig. 2 but showing a modified construction.

5. The cross bars 3 are generally fiat but I during the process of manufacture they are forced into the slots and portions thereof are permanently deformed into locking tongues 6 which secure the parts together.

The cross bars 3 have portions 4: which lie outside the edge girder bars 2. The portions 4C are bent at an angle to the body of the cross bars so as to lie in general parallelism and in contact with the edge girder bars 2". The end portions are bent around before the cross bars are forced into the slots. The bend is at the joint between the cross bar and the girder bar and is on a line substantially perpendicular to the plane of the grating surface. By reason of the fact that a locking tongue 6 is formed adjacent each end portion 4 during the assembling of the grating, the metal is bent to such shape that a particularly strong corner is secured.

Figure 2 shows the end portions 4 bent in such direction that the locking tongue is directed toward the body of the portion 4. Figure 3 shows a modified grating wherein the locking tongues are directed away from the body of the portions 4. Either form of joint is very strong and is efiective for holding the edge girder bar firmly in place. The structure is very solid and has no tendency to rattle or work loose.

It is generally desirable to use either the joint of Figure 2 on both edges of the grating or the joint of Figure 3 on both edges thereof. It will be understood therefore that the portions 4 may be directed the same Way on opposite edges of the grating or in opposite ways depending on whether there is an odd or even number of girder bars in the grating.

T have illustrated and described preferred forms of my invention as applied to a grating constructed according to my prior patent. Tt will be understood, however, that the invention is not limited to the forms shown as it may be otherwise embodied within the scope of the following claim.

I claim:

The method of making a grating which comprises forming a curved slot in a girder ban providing a cross bar of different cross sectional shape than theslot in the girder bar, and having an end portion extending at substantially right angles to the cross bar proper, placing the cross bar in such position relative to the girder bar that the end portion of the cross bar lies adjacent the plane of a side face of the girder bar, and forcing the cross bar into the slot whereby the end portion of the cross bar lies adjacent the girder bar, and that portion of the cross bar proper adjacent the bent over portion is permanently deformed by being forced into the slot.

In testimony whereof I have hereunto set my hand.

' HARRY NAGIN. 

